Controlling method for a washing machine

Patent metadata

Field	Value
Publication number	US-9417009-B2
Application number	US-201313782267-A
Country	US
Kind code	B2
Filing date	Mar 1, 2013
Priority date	Mar 6, 2012
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

A control method for a drying machine according to one exemplary embodiment is applied to a drying machine which selects at least one of a heat pump system and a heater to use as a heat source for heating air to be supplied into the drum. The control method includes activating the heat pump system when both of the heat pump system and the heater are selected as the heat source, and determining whether or not a compressor included in the heat pump system normally operates. Whether or not to use the heater as the heat source is decided according to whether or not the compressor normally operates.

First claim

What is claimed is:

1. A control method for a drying machine including a heat pump system and a heater for heating air to be supplied into a drum, and having a plurality of drying modes using the heat pump system and the heater individually or simultaneously, the method comprising:
activating the heat pump system when a drying mode using both of the heat pump system and the heater is selected; and
determining whether or not a filter, through which air discharged out of the drum flows, is blocked according to the temperature of air introduced into the drum after the activating of the heat pump system,
wherein the heater is activated or deactivated according to whether or not the filter is blocked,
wherein drying is executed using only the heat pump system as the heat source when a time point that the filter is determined to be blocked is after a predetermined time elapses from a drying start time point.

2. The method of claim 1 , wherein the heater is deactivated when the filter is determined to be blocked.

3. The method of claim 1 , wherein both of the heater and the heat pump system are activated when the filter is determined to be normal.

4. The method of claim 3 , further including:
re-determining whether or not the filter is blocked according to a temperature difference between the air introduced into the drum and the air discharged out of the drum when a predetermined time elapses after both of the heater and the heat pump system are activated, and deciding whether or not to use the heater and the heat pump system according to a result of the re-determination.

5. The method of claim 4 , wherein the re-determining as to whether or not the filter is blocked is configured to determine that the filter is blocked when the temperature difference between the air introduced into the drum and the air discharged out of the drum is more than a predetermined filter block reference temperature difference.

6. A control method for a drying machine including a heat pump system and a heater as heat sources for heating air to be supplied into a drum, the heat pump system including a compressor, a condenser, an evaporator, and an expansion valve, the method comprising:
activating the heat pump system when a drying mode using both of the heat pump system and the heater is selected;
determining whether or not the compressor of the heat pump system normally operates after the activating of the heat pump system;
deciding whether or not to use the heater according to whether or not the compressor normally operates,
determining whether or not a filter, through which air discharged out of the drum flows, is blocked according to the temperature of air introduced into the drum after the activating of the heat pump system,
wherein the heater is activated or deactivated according to whether or not the filter is blocked,
wherein drying is finished by cooling laundry accommodated in the drum when a time point that the filter is determined to be blocked is before a predetermined time elapses from a drying start time point.

7. The method of claim 6 , wherein the heater has a smaller heat supply capacity than the heat pump system.

8. The method of claim 6 , wherein the heater is also activated when the compressor normally operates.

9. The method of claim 6 , wherein the determining as to whether or not the compressor normally operates includes measuring a temperature variation of a refrigerant flowed through the compressor, wherein the compressor is determined to normally operate when the temperature variation of the refrigerant is more than a predetermined reference temperature variation.

10. The method of claim 6 , further including:
measuring the temperature of a refrigerant flowed through the compressor after the heater is activated; and
activating or deactivating the heater according to the measured temperature of the refrigerant.

11. The method of claim 10 , wherein the activating or deactivating of the heater includes:
deactivating the heater when the temperature of the refrigerant measured while the heater is activated reaches the upper limit of a predetermined temperature range;
measuring the temperature of the refrigerant flowed through the compressor while the heater is deactivated and determining whether or not the measured temperature is within the predetermined temperature range; and
reactivating the heater when the temperature of the refrigerant measured while the heater is deactivated reaches the lower limit of the predetermined temperature range.

12. The method of claim 6 , wherein the drying machine includes a cooling fan to suck external air, and
wherein the method further includes:
measuring the temperature of a refrigerant flowed through the compressor after the heater is activated; and
activating or deactivating the cooling fan according to the measured temperature of the refrigerant.

13. The method of claim 12 , wherein the activating or deactivating of the cooling fan includes:
activating the cooling fan when the temperature of the refrigerant measured while the heater is activated reaches an upper limit of a predetermined temperature range;
measuring the temperature of the refrigerant flowed through the compressor while the cooling fan is activated and determining whether or not the measured temperature is within the predetermined temperature range; and
deactivating the cooling fan when the temperature of the refrigerant measured while the cooling fan is activated reaches a lower limit of the predetermined temperature range.

14. The method of claim 6 , further including:
measuring the temperature of a refrigerant flowed through the compressor after the heater is activated; and
controlling the temperature of the refrigerant to be within an appropriate temperature range by controlling an open degree of the expansion valve of the heat pump system according to the measured temperature of the refrigerant.

15. The method of claim 14 , wherein the controlling of the open degree of the expansion valve includes:
a primary valve control step of controlling the open degree of the expansion valve within a predetermined first open degree range; and
a secondary valve control step of controlling the open degree of the expansion valve within a range larger than the first open degree range when the temperature of the refrigerant fails to belong to the appropriate temperature range even through the primary valve control step.

16. The method of claim 6 , further including:
measuring the temperature of air supplied into the drum or the temperature of air discharged out of the drum when both of the heat pump system and the heater are decided to be used;
activating or deactivating the heater according to whether or not the measured temperature of the air is within a predetermined temperature range; and
using only the heat pump system as the heat source when a number of times the heater is deactivated reaches a predetermined reference number of times.

17. The method of claim 16 , wherein the activating or deactivating of the heater includes:
deactivating the heater when the temperature of the air measured while the heater is activated reaches an upper limit of the temperature range;
measuring the temperature of the air supplied into the drum or the temperature of the air discharged out of the drum while the heater is deactivated and determining whether or not the measured temperature is within the temperature range; and
reactivating the heater when the temperature of the air measured while the heater is deactivated reaches a lower limit of the temperature range.

Assignees

• Lg Electronics Inc

Inventors

• Heo Seonil
• Lee Junseok
• Choe Woonje

Classifications

• F26B21/35

  Temperature; Pressure · CPC title

• F26B21/333 Primary

  by condensing the moisture in the drying medium, which may be recycled, e.g. using a heat pump cycle · CPC title

• D06F2103/50

  related to heat pumps, e.g. pressure or flow rate · CPC title

• D06F58/50

  Responding to irregular working conditions, e.g. malfunctioning of blowers · CPC title

• D06F2105/28

  Electric heating · CPC title